Friends of Dyke Marsh is a volunteer group dedicated to preserving, restoring and enhancing Dyke Marsh, a freshwater tidal marsh in Fairfax County on the Potomac River just south of Alexandria, Virginia. The Dyke Marsh Wildlife Preserve is administered by the National Park Service.

What Is Dyke Marsh?

The Dyke Marsh Wildlife Preserve is a freshwater, tidal marsh on the Virginia side of the Potomac River in Fairfax County. It is a unit of the George Washington Memorial Parkway, U.S. National Park Service. For more information, visit the NPS website at www.nps.gov/gwmp.

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FODM Membership Meetings

We have rescheduled our May 19 meeting for September 8. See below. Given the uncertainty posed by the coronavirus pandemic, we may have to make some changes. Check here and our Facebook page for updates.

Coming Events

On September 8 at 7:30 p.m., Dr. Christian Jones of George Mason University’s Potomac Science Center will give a presentation on wetlands types, trends, ecology and conservation at the Huntley Meadows Park Visitor Center, 3701 Lockheed Boulevard, Alexandria, VA 22306. An informal social will start at 7 p.m. Free.

Bird Walks Canceled Through June 10

*** NOTICE ***

In light of risks related to the coronavirus, the Friends of Dyke Marsh have canceled Sunday morning bird walks at Dyke Marsh starting March 15 and effective through June 10. We hope to resume walks on June 14. Check back here and our Facebook page for information on the future schedule.

Support FODM

Your contribution will help us preserve and restore Dyke Marsh and support special programs and studies. Thank you.

Support Dyke Marsh with Your Purchases

Amazon.com will donate .5 percent of the price of your purchases to the Friends of Dyke Marsh if you shop through smile.amazon.com. Click on the link and sign into your account or create an account.

Like Us on Facebook!

FODM is on Facebook. If you are already a Facebook member, just log in to your Facebook page and search for "Friends of Dyke Marsh". Or, click this icon and then "like" us:

Bienvenidos!

The Friends of Dyke Marsh extend a welcome to all of our friends. Click here for an invitation to the Dyke Marsh Wildlife Preserve in Spanish, which we hope will make Spanish-speaking visitors feel welcome. We hope to see you soon.

Event

Wintering Waterfowl

Tundra swan (Cygnus columbianus) Photo by Cathy Ledec.

FODM President Glenda Booth has an article in the January 2020 Zebra newspaper on waterfowl on the Potomac River in winter. Read the article here.

Loggerhead Shrikes

Sergio Harding banded the shrikes with a red band.

FODM President Glenda Booth published an article in the May-June 2018 Virginia Wildlife magazine, titled, “What’s Going on with the Butcher Bird? Visit the website here. Sightings of this bird in Northern Virginia are rare.

Water Chestnut

Water chestnut. Photo from MISC, Maryland Invasive Species Council.

Help Stop the Spread of a New Species of Water Chestnut

Be on the lookout for a new species of water chestnut (genus Trapa) (http://mdinvasives.org / iotm/june-2018/) found in the Potomac watershed, Trapa bispinosa Roxb. var. iinumai Nakano. It has been spreading since 1995 and is floating aquatic vegetation growing over the surface of a pond, lake or other fresh waterbody.

This species is identified by the seed cases having two spines instead of four found on Trapa natans. Report all invasive aquatic species to the US Geological Survey’s Nonindigenous aquatic species website (https://nas.er.usgs.gov / SightingReport.aspx).

Water chestnut (an annual) sprouts in May, spreads over the water surface and then flowers and fruits by July. It drops seeds all season until it senesces after a hard frost. To stop the spread, management by harvesting the plants by early July is very successful in eradicating the plants, but it may take several years of effort, if some seeds fall before the plants are harvested or lay dormant in the current year and sprout in a later year.